Classification of Organisms is done by Taxonomists - SYSTEMIC BIOLOGISTS
                                                                  Campbell - Concept Activities - chapter 1.2 - Classifying Schemes*.


      

Molecular evidence places all Living Organisms into... 3 DOMAINS*
NAS-8
                                         EUBACTERIA    -   true bacteria
                                         ARCHAEA          -   ancient prokaryotes (bacteria)
                                         EUCARYA          -    modern eukaryotes
  


Carl Woese(interview) established new divisions of life based upon molecular similarity of rRNA.
      
all cells are known to contain the same organelle - the ribosome, site of protein synthesis.
       he compared the nucleotide sequences of  small-unit rRNA from many species...
                   rRNA...  is FOUND in ALL cells with ribosome and therefore,
        if all cells are derived from a common progenitor[NAS-1], their rRNA sequence changes
        over evolutionary time can indicate divergence (loss of relatedness) through phylogeny.

 

 

 

 

 

 

 
  Woese described...
  

     the EUBACTERIA, as single celled life without nuclei
               are akin to common prokaryotes, but look similar to Archaea
   
     the ARCHAEA, as a prokaryotic-like group that
               thrive in extreme environments:          acid springs
                                                                       arctic ice,
                                                                       hydrothermal vents at deep oceans volcanoes,
                                                                       with crevices of solid rock in mines, etc....
               this group contains distinctive and varied chemical processes and a unique genetic makeup
  
    

     the EUCARYA, which emcompasses all life based upon cells with nuclei, inlcuding
               plants, animals, fungi, and single celled protists.

        by comparing similar & divergent sequences,the RNA phylogeny tree produced, a tree with
                      3 distinct branches (Domains)                    comparing the 3 Domains*later
 
                                                            

 

 

 

 

 

 


                                                                                                  
and within the more traditional divisions of life we describe the...                [Collage]
        5 KINGDOMS
 - a primary classification of organisms reflecting
                                 fundamental patterns of relationships in the natural world                

                                                   

           MONERA    -  single celled, microscopic bacteria;  most successful of all living organisms

           PROTISTA  -  algae/protozoans; unicellular eucaryotes

           PLANTAE    -  contains plants, photosynthetic organism with cellulosic cell walls

           FUNGI        -  contains molds, yeasts, & mushrooms, organisms that decompose dead organisms

           ANIMALIA -  kingdom that contains animals; organisms that eat other organisms &
                                                  lack cellulosic cell walls;   often motile
                                                                 
Campbell - Concept Activities - chapter 1.2 - Classifying Schemes*.

                         copyright c2008     Last update - Thursday, September 04, 2008
   back             Charles Mallery,    Biology 150, Department of Biology,   University of Miami,  Coral Gables, FL 33124